Microsoft .NET Framework 4.6 Preview

The Microsoft .NET Framework 4.6 is Microsoftâ€™s comprehensive and consistent programming model for building applications that have visually stunning user experiences, seamless and secure communication, and the ability to model a range of business processes. The .NET Framework redistributable package installs the .NET Framework runtime and associated files required to run applications developed to target the .NET Framework. The Microsoft .NET Framework 4.6 Preview is a highly compatible, in-place update to the Microsoft .NET Framework 4, .NET Framework 4.5, .NET Framework 4.5.1 and .NET Framework 4.5.2. The offline package can be used in situations where the web installer cannot be used due to lack of internet connectivity.

The newest version of the Microsoft .NET Framework 4.6. In Preview, the version number still appears in some places as 4.5.3. It will be updated to Microsoft .NET Framework 4.6 before the final version ships.

FEATURESBase class library changesAdded many new APIs to enable key scenarios, particularly cross platform scenarios. They include the following changes and additions:* New cryptography APIs such as AsymmetricAlgorithm.KeyExchangeAlgorithm, AsymmetricAlgorithm.SignatureAlgorithm, and System.Security.Cryptography.X509Certificates.X509Certificate.* Additional collections implement System.Collections.ObjectModel.ReadOnlyCollection, including System.Collections.Generic.Queue and System.Collections.Generic.Stack.* Additional members to support the task-based asynchronous pattern (TAP), including Task.CompletedTask and NamedPipeClientStream.ConnectAsync.

Support for code page encodings.NET Core primarily supports Unicode encodings, and by default it provides limited support for code page encodings. You can add support for code page encodings that are available in the .NET Framework but unsupported in .NET Core by registering code page encodings with the Encoding.RegisterProvider method. For more information, see CodePagesEncodingProvider.

Improvements to event tracingAn EventSource object can now be constructed directly, and you can call one of the Write() methods to emit a self-describing event.

Resizing in Windows Forms controlsThis feature has been expanded to include the System.Windows.Forms.DomainUpDown, System.Windows.Forms.NumericUpDown, System.Windows.Forms.DataGridViewComboBoxColumn, System.Windows.Forms.DataGridViewColumn and System.Windows.Forms.ToolStripSplitButton types.This is an opt-in feature. To enable it, set the EnableWindowsFormsHighDpiAutoResizing element to true in the application configuration (app.config) file.

64-bit JIT compiler for managed codeThis release includes a new version of the 64-bit JIT Compiler, which provides significant performance improvements over the legacy 64bit JIT Compiler. While we have tried to make the transition to the new Compiler as transparent as possible, you may see changes in behavior.

Support for converting DateTime to or from Unix timeNew methods have been added to support converting DateTime to or from Unix time. The following APIs have been added to DateTimeOffset:* static DateTimeOffset FromUnixTimeSeconds(long seconds)* static DateTimeOffset FromUnixTimeMilliseconds(long milliseconds)* long ToUnixTimeSeconds()* long ToUnixTimeMilliseconds()

ASP.NET Model Binding supports Task returning methodsASP.NET Model Binding methods that were previously Task returning were not supported and threw an exception at runtime if configured. If applications are deployed with such methods, these methods will now be executed correctly. This change applies only to applications specifically targeting Microsoft .NET Framework 4.6 or later.